A conventional FlexRay transceiver includes a FlexRay transmitter and a FlexRay receiver, the FlexRay transmitter includes a current mirror and a transmission gate, and the FlexRay receiver includes a hysteresis comparator, a window comparator and a charge-discharge pump. The transmission gate determines whether the current mirror generates a current according to a state code so as to provide voltage signals to a bus. The hysteresis comparator is used for comparison between a first input voltage and a second input voltage, and an output signal is generated based on comparison result. The window comparator is in connection with the hysteresis comparator. When the first input voltage and the second input voltage is within a voltage range, the window comparator outputs an idle state signal. The charge-discharge pump is in connection with the window comparator. The charge-discharge pump is used to eliminate the noise of the idle state signal. However, the conventional FlexRay transceiver does not possess the function of over current detection, when the internal current of the transceiver is excessive, the transceiver is not able to detect the condition of over current therefore leading to damage. Besides, the conventional FlexRay transceiver does not possess the function of wake up detection. Once conventional FlexRay transceiver is applicable to FlexRay-based in-car communication system, the operation mode of the transceiver can not be switched flexibly between low power mode and normal mode. Therefore, additional power consumption is occurred.